Effects of ground motion intensity parameters on soil-foundation-structure-interaction and site response

摘要

The seismic response of a structure is strongly influenced by the properties of the earthquake motion experienced at its foundation, which is in turn influenced by Soil-Foundation-Structure-Interaction (SFSI) effects. The characteristics of the suite of ground motions selected for design affect the site's nonlinear response as well as the interaction between soil, foundation, and structure in analyses. In this study, dynamic centrifuge experiments were conducted on a Single-Degree-of-Freedom (SDOF) model building founded on dry, medium-dense sand inside a Flexible-Shear-Beam (FSB) container. A series of six earthquake motions with different characteristics was applied to the base of the container as input to the soil-structure system and the effects of Peak Ground Acceleration (PGA), Arias Intensity (I_a), and Shaking Intensity Rate (SIR) on different aspects of SFSI and site response were evaluated. More holistic intensity parameters, i.e. Arias Intensity and Shaking Intensity Rate, showed more consistent effects especially on site response and structural inertial response. In addition, the importance of index parameters containing both effects of intensity and frequency content is emphasized.